Aluminum/Magnesium Hydroxide Stearate

Aluminum/Magnesium Hydroxide Stearate is primarily an opacifier/thickener and slip agent used at low levels in powders and creams, and it is generally considered inert with low reactivity on intact skin. Clinical experience and patch testing trends suggest irritation is uncommon, but in eczema-prone or heavily compromised barriers, particulate/metal-soap residues can occasionally contribute to dryness or stinging, so it is best rated as very gentle rather than completely inert for high-sensitivity populations. Safety Notes: Aluminum/Magnesium Hydroxide Stearate is used mainly as a suspending/anti-caking and texture-modifying agent in emulsions and anhydrous systems; in many mainstream leave-on lotions, sunscreens, and color cosmetics it appears at very low levels (~0.05–0.5%) to stabilize pigments/UV filters and improve slip. Higher consumer-available levels (typically ~2–8%) are seen in high-structure sticks/compacts and heavy pigment or mineral UV filter dispersions where it functions as a key gellant/suspending aid; above this, products generally become overly waxy/draggy and are uncommon in OTC skincare. It is not subject to a specific EU/FDA maximum like aluminum salts used as antiperspirant actives, so observed limits are largely driven by sensorial and stability constraints rather than regulation.